Coupler for use in oxidative hair dyeing

ABSTRACT

Couplers for hair coloring compositions for oxidative dyeing of hair are compounds of formula (1):                    
     wherein X is selected from of halogen and R 5 SO 4  R 3  is selected from C 1  to C 2  alkyl and hydroxyethyl; and R, R 1 , R 2  and R 5  are each independently selected from C 1  to C 22  alkyl or C 1  to C 22  mono or dihydroxyalkyl.

This patent application is a divisional application of U.S. patentapplication Ser. No. 09/993,210 filed Nov. 16, 2001 now U.S. Pat. No.6,589,295 and claims the benefit of U.S. Provisional Patent ApplicationSerial No. 60/249,831 filed Nov. 17, 2000.

FIELD OF THE INVENTION

This invention relates to novel couplers for use in hair coloringcompositions comprising one or more oxidative hair coloring agents incombination with one or more oxidizing agents. The invention alsorelates to hair coloring compositions of these novel couplers and tocoloring or dyeing of hair using compositions containing these couplers.

BACKGROUND OF THE INVENTION

Coloration of hair is a procedure practiced from antiquity employing avariety of means. In modern times, the most extensively used methodemployed to color hair is to color hair by an oxidative dyeing processemploying hair coloring systems utilizing one or more oxidative haircoloring agents in combination with one or more oxidizing agents.

Most commonly a peroxy oxidizing agent is used in combination with oneor more oxidative hair coloring agents, generally small moleculescapable of diffusing into hair and comprising one or more primaryintermediates and one or more couplers. In this procedure, a peroxidematerial, such as hydrogen peroxide, is employed to activate the smallmolecules of primary intermediates so that they react with couplers toform larger sized compounds in the hair shaft to color the hair in avariety of shades and colors.

A wide variety of primary intermediates and couplers have been employedin such oxidative hair coloring systems and compositions. Among theprimary intermediates employed there may be mentionedp-phenylenediamine, p-toluenediamine, p-aminophenol,4-amino-3-methylphenol, and as couplers there may be mentionedresorcinol, 2-methylresorcinol, 3-aminophenol, and5-amino-2-methylphenol. A majority of the shades have been produced withdyes based on p-phenylenediamine.

For providing an orange coloration to hair 2-methyl-5-aminophenol hasbeen extensively used in combination with p-aminophenol as a primaryintermediate. However, the resulting orange color on hair undergoessignificant changes on exposure to light or shampooing. U.S. Pat. No.4,065,255 and EP patent publications EP 634165 A1 and EP 667143 A1suggest the use of 2-methyl-5-N-hydroxyethylaminophenol,2-methyl-5-alkylaminophenol and 2-methyl-5-aminophenol as couplers.Therefore, there is a need for new orange couplers for use in oxidativehair dyeing compositions and systems.

BRIEF SUMMARY OF THE INVENTION

This invention provides novel couplers of the formula (1)

X is selected from halogen and R⁵SO₄ where the halogen is preferably Cl,Br or I; R³ is selected from C₁ to C₂ alkyl and hydroxyethyl; and R, R¹,R² and R⁵ are each independently selected from C₁ to C₂₂ alkyl or C₁ toC₂₂ mono or dihydroxyalkyl. These novel couplers are used to providecoloration to hair in which there is good dye uptake by the hair andprovides shades or colors which are stable over a relatively long periodof time. The novel couplers provide for dyeing of hair that providescolor or shades that possess good wash fastness and do not undergo thesignificant changes on exposure to light or shampooing as experiencedwith 2-methyl-5-aminophenol.

DETAILED DESCRIPTION OF THE INVENTION

Preferred coupler compounds of this invention are those of formula (1)

wherein is Cl, Br, I or R⁵SO₄ where R⁵ is C₁ to C₃ alkyl; and R, R¹ andR² are each independently C₁ to C₃ alkyl, most preferably methyl.

Especially preferred couplers of this invention are the followingcompounds:

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumiodide;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumchloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniummethyl sulfate;

{4-[3-hydroxy-4-hyrroxyethyl-phenylamino)-methyl]-phenyl}-trimethylammonium chloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-triethyl ammoniumchloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-tripropyl ammoniumpropyl sulfate;

{4-[3-hydroxy-4-ethyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumchloride; and

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumbromide.

The compounds of formula (1) of this invention are readily preparedaccording to the following reaction sequence.

In the reaction sequence a reductive amination of an aminophenol offormula (2) with a disubstituted benzaldehyde of formula (3) in thepresence of a reducing agent such as sodium triacetoxyborohydride orsodium cyanoborohydride in 1% acetic acid in 1,2-dichloroethane producesa compound of formula (4). Reaction of the compound of formula (4) withthe quaternization agent R-X in dimethylforamide (DMF) gives a compoundof formula (1) of this invention where X, R, R¹, R² and R³ are asdefined hereinbefore.

EXAMPLE 1 Synthesis of{4-[(3-Hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl AmmoniumChloride 7

To a solution of 4-dimethylaminobenzaldehyde 1 (14.8 g, 100 mmol) inmethanol (250 mL) (Scheme 1) were added 5-amino-2-methyl-phenol 2 (14.8g, 120 mmol) and sodium cyanoborohydride (19.0 g, 300 mmol). Thereaction mixture was stirred at room temperature for 3 d. The reactionmixture was evaporated and water was added. The mixture was extractedwith ethyl acetate, washed with brine and dried over MgSO₄, filtered andevaporated to give a crude orange solid. This crude solid wasrecrystallized from hot ethyl acetate and hexane to yield5-(4-dimethylamino-benzylamino)-2-methyl-phenol 3 as a tan solid (2.34g, 9% yield): ¹H NMR (400 MHz, DMSO-d₆) δ 1.91 (s, 3H) 2.82 (s, 6H),4.01 (d, J=5.5 Hz, 2H), 5.67 (s, 1H), 5.93 (d, J=7.5 Hz, 1H), 6.04 (s,1H), 6.65 (m, 2H), 7.12 (d, J=8.2 Hz, 2H), 8.74 (s, 1H); ¹³C NMR (400MHz, DMSO-d₆) δ 15.6, 40.7, 46.6, 87.0, 99.9, 104.0, 111.1, 112.8,128.3, 130.8, 148.4, 149.8, 156.0. To a solution of 3 (0.64 g, 2.5 mmol)in anhydrous THF (25 mL) were added 4-dimethylaminopyridine (0.31 g, 2.5mmol) and di-tertbutyl dicarbonate (B_(OC) ₂ O) (2.18 g, 10 mmol). Thereaction mixture was stirred at room temperature for 18 h. The solventwas evaporated and the residue was taken up into ethyl acetate (25 mL)and water (25 mL). The organic phase was washed with brine (25 mL),dried over MgSO₄, filtered and evaporated to give a crude orange solid.This solid was recrystallized from hot ethanol and water to yield acarbonic acid tert-butyl ester compound 4 as a tan solid (1.17 g, 33%yield): ¹H NMR (400 MHz, DMSO-d₆) δ 1.45 (s, 9H), 1.91 (s, 3H), 2.88 (s,6H), 4.06 (d, J=5.7 Hz, 2H), 6.03 (t, J=5.7 Hz, 1H), 6.28 (s, 1H), 6.38(dd, J=2.0, 8.1 Hz, 1H), 6.66 (d,J=8.6 Hz, 2H), 6.88 (d, J=8.3 Hz, 1H),7.14 (d, J=8.5 Hz, 2H); ¹³C NMR (400 MHz, DMSO-d₆) δ 15.0, 27.6, 39.1,46.5, 83.0, 105.9, 110.5, 112.8, 116.0, 127.6, 128.5, 131.3, 148.6,149.9, 150.1, 151.4. To a solution of 4 (0.36 g, 1.0 mmol) in anhydrousTHF (10 mL) was added di-tertbutyl dicarbonate (0.87 g, 4.0 mmol). Thereaction mixture was stirred at 40° C. for 18 h. The solvent wasevaporated and the residue was taken up into ethyl acetate (25 mL) andwater (25 mL). The organic phase was washed with brine (10 mL), driedover MgSO₄, filtered and evaporated to afford compound 5 as an orangeoil (0.29 g, 62% yield): ¹H NMR (400 MHz, DMSO-d₆) δ 1.37 (s, 9H), 1.46(s, 9H), 2.05 (s, 3H), 2.83 (s, 6H), 4.67 (s, 2H), 6.61 (d, J=8.3 Hz,2H), 6.95 (m, 4H), 7.15 (d, J=7.7 Hz, 1H); ¹³C NMR (400 MHz, DMSO-d₆) δ14.7, 23.6, 26.8, 27.0, 27.5, 79.5, 82.8, 111.9, 123.6, 125.0, 126.4,127.8, 130.1, 140.5, 145.9, 148.3, 149.2150.4, 153.4. To a solution of 5(0.23 g, 0.49 mmol) in anhydrous DMF (5 mL) was added iodomethane (0.18mL, 2.96 mmol). The reaction mixture was stirred at room temperature for3 d. Diethyl ether (50 mL) was added, stirred overnight and decanted toyield compound 6 as an orange solid (137 mg, 47% yield): ¹H NMR (400MHz, DMSO-d₆) δ 1.38 (s, 9H), 1.47 (s, 9H), 2.06 (s, 3H), 3.55 (s, 9H),7.05 (dd, J=2.0, 8.1 Hz, 1H), 7.06 (s, 1H), 7.20 (d, J=8.3 Hz, 1H), 7.42(d, J=8.9 Hz, 2H), 7.89 (d, J=7.9 Hz, 2H); ¹³C NMR (400 MHz, DMSO-d₆) δ15.4, 27.5, 28.2, 52.0, 56.7, 80.8, 83.6, 115.0, 119.9, 120.9, 123.0,127.5, 128.5, 131.1, 134.0, 140.9, 146.0, 149.1, 151.1. The compound 6(120 mg, 0.20 mmol) was dissolved in 4N hydrogen chloride in dioxane(0.5 mL, 2.0 mmol) and stirred at room temperature for 3 d. The solventwas evaporated and diethyl ether (5 mL) was added. The resultingprecipitate was filtered to yield{4-[(3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl-ammoniumchloride 7 as a dark orange solid (60 mg, 98% yield): ¹H NMR (400 MHz,DMSO-d₆) δ 1.94 (s, 3H), 3.56 (s, 9H), 4.30 (s, 2H), 6.06 (s, 1H), 6.20(bs, 1H), 6.74 (m, 1H), 7.57 (d, J=8.6 Hz, 2H), 7.89 (d, J=8.9 Hz, 2H),9.07 (s,1H); ¹³C NMR (400 MHz, DMSO-d₆) δ 15.9, 56.7, 66.7, 110.0,113.5, 120.7, 122.1, 131.2, 132.0, 128.0, 138.0, 157.0, 193.0; MS (M)⁺:271.

EXAMPLES 2 TO 8

Employing the applicable aminophenol, disubstituted aminobenzaldehydeand R-X reagents in the forgoing described synthesis procedure thefollowing coupler compounds of this invention are prepared:

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumiodide;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniummethyl sulfate;

{4-[3-hydroxy-4-hydroxyethyl-phenylamino)-methyl]-phenyl}-trimethylammonium chloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-triethyl ammoniumchloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-tripropyl ammoniumpropyl sulfate;

{4-[3-hydroxy-4-ethyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumchloride; and

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumbromide.

Hair coloring compositions of this invention can contain the novelcouplers of this invention as the sole coupler or can also contain othercouplers in combination with primary intermediates.

For hair coloring compositions of this invention, there may be used oneor more suitable primary intermediates in combination with the novelcouplers of this invention. Suitable primary intermediates include, forexample,

p-phenylenediamine derivatives such as: benzene-1,4-diamine (commonlyknown as p-phenylenediamine), 2-methyl-benzene-1,4-diamine,2-chloro-benzene-1,4-diamine, N-phenyl-benzene-1,4-diamine,N-(2-ethoxyethyl)benzene-1,4-diamine,2-[(4-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol, (commonly known asN,N-bis(2-hydroxyethyl)-p-phenylenediamine)(2,5-diamino-phenyl)-methanol, 1-(2,5-diamino-phenyl)-ethanol,2-(2,5-diamino-phenyl)-ethanol, N-(4-aminophenyl)benzene-1,4-diamine,2,6-dimethyl-benzene-1,4-diamine, 2-isopropyl-benzene-1,4-diamine,1-[(4-aminophenyl)amino]-propan-2-ol, 2-propyl-benzene-1,4-diamine,1,3-bis[(4-aminophenyl)(2-hydroxyethyl)amino]propan-2-ol, N⁴,N⁴,2-trimethylbenzene-1,4-diamine, 2-methoxy-benzene-1,4-diamine,1-(2,5-diaminophenyl)ethane-1,2-diol, 2,3-dimethyl-benzene-1,4-diamine,N-(4-amino-3-hydroxy-phenyl)-acetamide, 2,6-diethylbenzene-1,4-diamine,2,5-dimethylbenzene-1,4-diamine, 2-thien-2-ylbenzene-1,4-diamine,2-thien-3-ylbenzene-1,4-diamine, 2-pyridin-3-ylbenzene-1,4-diamine,1,1′-biphenyl-2,5-diamine, 2-(methoxymethyl)benzene-1,4-diamine,2-(aminomethyl)benzene-1,4-diamine, 2-(2,5-diaminophenoxy)ethanol,N-[2-(2,5-diaminophenoxy)ethyl]-acetamide,N,N-dimethylbenzene-1,4-diamine, N,N-diethylbenzene-1,4-diamine,N,N-dipropylbenzene-1,4-diamine, 2-[(4-aminophenyl)(ethyl)amino]ethanol,2-[(4-amino-3-methyl-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol,N-(2-methoxyethyl)-benzene-1,4-diamine,3-[(4-aminophenyl)amino]propan-1-ol,3-[(4-aminophenyl)-amino]propane-1,2-diol,N-{4-[(4-aminophenyl)amino]butyl}benzene-1,4-diamine, and2-[2-(2-{2-[(2,5-diaminophenyl)-oxy]ethoxy}ethoxy)ethoxy]benzene-1,4-diamine;

p-aminophenol derivatives such as: 4-amino-phenol (commonly known asp-aminophenol), 4-methylamino-phenol, 4-amino-3-methyl-phenol,4-amino-2-hydroxymethyl-phenol, 4-amino-2-methyl-phenol,4-amino-2-[(2-hydroxy-ethylamino)-methyl]-phenol,4-amino-2-methoxymethyl-phenol, 5-amino-2-hydroxy-benzoic acid,1-(5-amino-2-hydroxy-phenyl)-ethane-1,2-diol,4-amino-2-(2-hydroxy-ethyl)-phenol, 4-amino-3-(hydroxymethyl)phenol,4-amino-3-fluoro-phenol, 4-amino-2-(aminomethyl)-phenol, and4-amino-2-fluoro-phenol;

o-aminophenol derivatives such as: 2-amino-phenol (commonly known aso-aminophenol), 2,4-diaminophenol, 2-amino-5-methyl-phenol,2-amino-6-methyl-phenol, N-(4-amino-3-hydroxy-phenyl)-acetamide, and2-amino-4-methyl-phenol; and

heterocyclic derivatives such as: pyrimidine-2,4,5,6-tetramine (commonlyknown as 2,4,5,6-tetraaminopyridine), 1-methyl-1H-pyrazole-4,5-diamine,2-(4,5-diamino-1H-pyrazol-1-yl)ethanol,N²,N²-dimethyl-pyridine-2,5-diamine,2-[(3-amino-6-methoxypyridin-2-yl)amino]ethanol,6-methoxy-N²-methyl-pyridine-2,3-diamine,2,5,6-triaminopyrimidin-4(1H)-one, pyridine-2,5-diamine,1-isopropyl-1H-pyrazole-4,5-diamine,1-(4-methylbenzyl)-1H-pyrazole-4,5-diamine,1-(benzyl)-1H-pyrazole-4,5-diamine and1-(4-chlorobenzyl)-1H-pyrazole-4,5-diamine.

The couplers of formula (1) of this invention may be used with anysuitable coupler(s) in hair coloring compositions or systems of thisinvention.

Suitable known couplers include, for example:

phenols, resorcinol and naphthol derivatives such as:naphthalene-1,7-diol, benzene-1,3-diol, 4-chlorobenzene-1,3-diol,naphthalen-1-ol, 2-methyl-naphthalen-1-ol, naphthalene-1,5-diol,naphthalene-2,7-diol, benzene-1,4-diol, 2-methyl-benzene-1,3-diol,7-amino-4-hydroxy-naphthalene-2-sulfonic acid,2-isopropyl-5-methylphenol, 1,2,3,4-tetrahydro-naphthalene-1,5-diol,2-chloro-benzene-1,3-diol, 4-hydroxy-naphthalene-1-sulfonic acid,benzene-1,2,3-triol, naphthalene-2,3-diol,5-dichloro-2-methylbenzene-1,3-diol, 4,6-dichlorobenzene-1,3-diol, and2,3-dihydroxy-[1,4]naphthoquinone;

m-phenylenediamines such as: 2,4-diaminophenol, benzene-1,3-diamine,2-(2,4-diamino-phenoxy)-ethanol,2-[(3-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol,2-mehyl-benzene-1,3-diamine,2-[[2-(2,4-diamino-phenoxy)-ethyl]-(2-hydroxy-ethyl)-amino]-ethanol,4-{3-[(2,4-diaminophenyl)oxy]propoxy}benzene-1,3-diamine,2-(2,4-diamino-phenyl)-ethanol,2-(3-amino-4-methoxy-phenylamino)-ethanol,4-(2-amino-ethoxy)-benzene-1,3-diamine, (2,4-diamino-phenoxy)-aceticacid, 2-[2,4-diamino-5-(2-hydroxy-ethoxy)-phenoxy]-ethanol,4-ethoxy-6-methyl-benzene-1,3-diamine,2-(2,4-diamino-5-methyl-phenoxy)-ethanol,4,6-dimethoxy-benzene-1,3-diamine,2-[3-(2-hydroxy-ethylamino)-2-methyl-phenylamino]-ethanol,3-(2,4-diamino-phenoxy)-propan-1-ol, N-[3-(dimethylamino)phenyl]urea,4-methoxy-6-methylbenzene-1,3-diamine,4-fluoro-6-methylbenzene-1,3-diamine,2-({3-[(2-hydroxyethyl)amino]-4,6-dimethoxyphenyl}-amino)ethanol,3-(2,4-diaminophenoxy)-propane-1,2-diol,2-[2-amino-4-(methylamino)-phenoxy]ethanol,2-[(5-amino-2-ethoxy-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol,2-[(3-aminophenyl)amino]ethanol, N-(2-aminoethyl)benzene-1,3-diamine,4-{[(2,4-diamino-phenyl)oxy]methoxy}-benzene-1,3-diamine, and2,4-dimethoxybenzene-1,3-diamine;

m-aminophenols such as: 3-amino-phenol,2-(3-hydroxy-4-methyl-phenylamino)-acetamide,2-(3-hydroxy-phenylamino)-acetamide, 5-amino-2-methyl-phenol,5-(2-hydroxy-ethylamino)-2-methyl-phenol, 5-amino-2,4-dichloro-phenol,3-amino-2-methyl-phenol, 3-amino-2-chloro-6-methyl-phenol,5-amino-2-(2-hydroxy-ethoxy)-phenol,2-chloro-5-(2,2,2-trifluoro-ethylamino)-phenol,5-amino-4-chloro-2-methyl-phenol, 3-cyclopentylamino-phenol,5-[(2-hydroxyethyl)amino]-4-methoxy-2-methylphenol,5-amino4-methoxy-2-methylphenol, 3-(dimethylamino)phenol,3-(diethylamino)phenol, 5-amino-4-fluoro-2-methylphenol,5-amino-4-ethoxy-2-methylphenol, 3-amino-2,4-dichloro-phenol,3-[(2-methoxyethyl)amino]phenol, 3-[(2-hydroxyethyl)amino]phenol,5-amino-2-ethyl-phenol, 5-amino-2-methoxyphenol,5-[(3-hydroxypropyl)amino]-2-methylphenol,3-[(3-hydroxy-2-methylphenyl)-amino]propane-1,2-diol, and3-[(2-hydroxyethyl)amino]-2-methylphenol; and

heterocyclic derivatives such as: 3,4-dihydro-2H-1,4-benzoxazin-6-ol,4-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one,6-methoxyquinolin-8-amine, 4-methylpyridine-2,6-diol,2,3-dihydro-1,4-benzodioxin-5-ol, 1,3-benzodioxol-5-ol,2-(1,3-benzodioxol-5-ylamino)ethanol, 3,4-dimethylpyridine-2,6-diol,5-chloropyridine-2,3-diol, 2,6-dimethoxypyridine-3,5-diamine,1,3-benzodioxol-5-amine,2-{[3,5-diamino-6-(2-hydroxy-ethoxy)-pyridin-2-yl]oxy}-ethanol,1H-indol-4-ol, 5-amino-2,6-dimethoxypyridin-3-ol, 1H-indole-5,6-diol,1H-indol-7-ol, 1H-indol-5-ol, 1H-indol-6-ol,6-bromo-1,3-benzodioxol-5-ol, 2-aminopyridin-3-ol, pyridine-2,6-diamine,3-[(3,5-diaminopyridin-2-yl)oxy]propane-1,2-diol,5-[(3,5-diaminopyridin-2-yl)oxy]pentane-1,3-diol, 1H-indole-2,3-dione,indoline-5,6-diol, 3,5-dimethoxypyridine-2,6-diamine,6-methoxypyridine-2,3-diamine, and3,4-dihydro-2H-1,4-benzoxazin-6-amine.

Preferred primary intermediates include:

p-phenylenediamine derivatives such as: 2-methyl-benzene-1,4-diamine,benzene-1,4-diamine, 1-(2,5-diamino-phenyl)-ethanol,2-(2,5-diamino-phenyl)-ethanol, N-(2-methoxyethyl)benzene-1,4-diamine,2-[(4-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol, and1-(2,5-diaminophenyl)ethane-1,2-diol;

p-aminophenol derivatives such as 4-amino-phenol, 4-methylamino-phenol,4-amino-3-methyl-phenol, 4-amino-2-methoxymethyl-phenol, and1-(5-amino-2-hydroxy-phenyl)-ethane-1,2-diol;

o-aminophenol derivatives such as: 2-amino-phenol,2-amino-5-methyl-phenol, 2-amino-6-methyl-phenol,N-(4-amino-3-hydroxy-phenyl)-acetamide, and 2-amino-4-methyl-phenol;

heterocyclic derivatives such as: pyrimidine-2,4,5,6-tetramine,1-methyl-1H-pyrazole-4,5-diamine,2-(4,5-diamino-1H-pyrazol-1-yl)ethanol,1-(4-methylbenzyl)-1H-pyrazole-4,5-diamine,1-(benzyl)-1H-pyrazole-4,5-diamine andN²,N²-dimethyl-pyridine-2,5-diamine.

Preferred couplers include:

phenols, resorcinol and naphthol derivatives such as:naphthalene-1,7-diol, benzene-1,3-diol, 4-chlorobenzene-1,3-diol,naphthalen-1-ol, 2-methyl-naphthalen-1-ol, naphthalene-1,5-diol,naphthalene-2,7-diol, benzene-1,4-diol, 2-methyl-benzene-1,3-diol, and2-isopropyl-5-methylphenol;

m-phenylenediamines such as: benzene-1,3-diamine,2-(2,4-diamino-phenoxy)-ethanol,4-{3-[(2,4-diaminophenyl)oxy]propoxy}benzene-1,3-diamine,2-(3-amino-4-methoxy-phenylamino)-ethanol,2-[2,4-diamino-5-(2-hydroxy-ethoxy)-phenoxy]-ethanol, and3-(2,4-diamino-phenoxy)-propan-1-ol;

m-aminophenols such as: 3-amino-phenol, 5-amino-2-methyl-phenol,5-(2-hydroxy-ethylamino)-2-methyl-phenol, and 3-amino-2-methyl-phenol;and

heterocyclic derivatives such as: 3,4-dihydro-2H-1,4-benzoxazin-6-ol,4-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, 1,3-benzodioxol-5-ol,1,3-benzodioxol-5-amine, 1H-indol-4-ol, 1H-indole-5,6-diol,1H-indol-7-ol, 1H-indol-5-ol, 1H-indol-6-ol, 1H-indole-2,3-dione,pyridine-2,6-diamine, and 2-aminopyridin-3-ol.

Most preferred primary intermediates include:

p-phenylenediamine derivatives such as: 2-methyl-benzene-1,4-diamine,benzene-1,4-diamine, 2-(2,5-diamino-phenyl)-ethanol,1-(2,5-diamino-phenyl)-ethanol, and2-[(4-amino-phenyl)-(2-hydroxy-ethyl)-amino]-ethanol;

p-aminophenol derivatives such as: 4-amino-phenol, 4-methylamino-phenol,4-amino-3-methyl-phenol, and1-(5-amino-2-hydroxy-phenyl)-ethane-1,2-diol;

o-aminophenols such as: 2-amino-phenol, 2-amino-5-methyl-phenol,2-amino-6-methyl-phenol, and N-(4-amino-3-hydroxy-phenyl)-acetamide; and

heterocyclic derivatives such as: pyrimidine-2,4,5,6-tetramine,2-(4,5-diamino-1H-pyrazol-1-yl)ethanol,1-(4-methylbenzyl)-1H-pyrazole-4,5-diamine, and1-(benzyl)-1H-pyrazole-4,5-diamine.

Most preferred couplers include:

phenols, resorcinol and naphthol derivatives such as: benzene-1,3-diol,4-chlorobenzene-1,3-diol, naphthalen-1-ol, 2-methyl-naphthalen-1-ol, and2-methyl-benzene-1,3-diol;

m-phenylenediamine such as: 2-(2,4-diamino-phenoxy)-ethanol,2-(3-amino-4-methoxy-phenylamino)-ethanol,2-[2,4-diamino-5-(2-hydroxy-ethoxy)-phenoxy]-ethanol, and3-(2,4-diamino-phenoxy)-propan-1-ol;

m-aminophenols such as: 3-amino-phenol, 5-amino-2-methyl-phenol,5-(2-hydroxy-ethylamino)-2-methyl-phenol, and 3-amino-2-methyl-phenol;and

heterocyclic derivatives such as: 3,4-dihydro-2H-1,4-benzoxazin-6-ol,4-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, and 1H-indol-6-ol, and2-aminopyridin-3-ol.

Understandably, the coupler compounds and the primary intermediatecompounds, as well as the other dye compounds, in so far as they arebases, can be used as free bases or in the form of their physiologicallycompatible salts with organic or inorganic acids, such as hydrochloricacid or sulfuric acid, or, in so far as they have aromatic OH groups, inthe form of their salts with bases, such as alkali phenolates.

The total amount of the combination of dye precursors (e.g., primaryintermediate and coupler compounds) in the hair coloring compositions orsystems of this invention is generally from about 0.001 to about 10,preferably from about 0.02 to about 10, and most preferably from about0.2 to about 6.0 weight percent based on the total weight of the haircoloring composition. The primary intermediate and coupler compounds aregenerally used in equivalent amounts. However, it is possible to use theprimary intermediate compounds in either excess or deficiency, i.e., amolar ratio of primary intermediate to coupler generally ranging fromabout 5:1 to about 1:5.

The hair coloring compositions of this invention will contain thecouplers of this invention in an effective coloring amount, generally inan amount of from about 0.001 to about 6 weight percent by weight of thehair dye composition, preferably from about 0.01 to about 3.5 weightpercent. Other couplers, when present, are typically present in anamount such that in aggregate the concentration of couplers in thecomposition is from about 0.01 to about 6 weight percent. The primaryintermediate(s) is present in an effective dyeing concentrationgenerally an amount of from about 0.001 to about 6.0 weight percent byweight of the hair dye composition, preferably from about 0.01 to about3.5 weight percent. Any suitable carrier or vehicle, generally anaqueous or hydroalcoholic solution, can be employed, preferably anaqueous solution. The carrier or vehicle will generally comprise up toabout 40 weight percent.

The hair coloring compositions of this invention may contain one or morecationic, anionic or amphoteric surface active agents, perfumes,antioxidants, sequestering agents, thickening agents, alkalizing oracidifying agents, and other dyeing agents.

The compositions of the present invention are used by admixing them witha suitable oxidant, which reacts with the hair dye precursors to developthe hair dye. Any suitable peroxide providing agent can be employed inthe coloring compositions of this invention, particularly hydrogenperoxide (H₂O₂) or precursors therefor. Also suitable are urea peroxide,sodium perborate, sodium percarbonate, and melamine peroxide.

Moreover, cosmetic additive ingredients, which are commonly used incompositions for coloring hair, can be used in the hair coloringcompositions according to the invention, for example antioxidants, suchas ascorbic acid, thioglycolic acid or sodium sulfite, and perfume oils,complex formers, wetting agents, emulsifiers, thickeners and carematerials.

The form of the hair coloring compositions according to the inventioncan be, for example, a solution, especially an aqueous oraqueous-alcoholic solution. However, the form that is particularlypreferred is a cream, gel or an emulsion. Its composition is a mixtureof the dye ingredients with the conventional cosmetic additiveingredients suitable for the particular preparation.

Conventional cosmetic additive ingredients in solutions, creams,emulsion or gels include, for example:

Solvents: In addition to water, solvents that can be used are loweralkanols (e.g., ethanol, propanol, isopropanol); polyols (e.g.,carbitols, propylene glycol, glycerin). Under suitable processing,higher alcohols, such as cetyl alcohol, are suitable organic solvents,provided they are first liquified by melting, typically at lowtemperature (50 to 80° C.), before incorporation of other, usuallylipophilic, materials. See WO 98/27941 (section on diluents)incorporated by reference.

Anionic and Nonionic Surfactants: These materials are from the classesof anionic, cationic, amphoteric or nonionic surfactant compounds, suchas fatty alcohol sulfates, ethoxylated fatty alcohol sulfates,alkylsulfonates, alkylbenzensulfonates, alkyltrimethylammonium salts,alkylbetaines, ethoxylated fatty alcohols, ethoxylated nonylphenols,fatty acid alkanol amides and ethoxylated fatty acid esters. They areincluded for various reasons, e.g., to assist in thickening, for formingemulsions, to help in wetting hair during application of the hair dyecomposition, etc. Suitable materials are alkyl sulfates, ethoxylatedalkyl sulfates, alkyl glyceryl ether sulfonates, methyl acyl taurates,acyl isethionates, alkyl ethoxy carboxylates, fatty acid mono- anddiethanolamides. Reference is made to WO 98/52523 published Nov. 26,1998 and incorporated herein by reference.

Thickeners: Suitable thickeners include such as higher fatty alcohols,starches, cellulose derivatives, petrolatum, paraffin oil, fatty acidsand anionic and nonionic polymeric thickeners based on polyacrylic andpolyurethane polymers. Examples are hydroxyethyl cellulose,hydroxymethylcellulose and other cellulose derivatives, hydrophobicallymodified anionic polymers and nonionic polymers, particularly suchpolymers having both hydrophilic and hydrophobic moieties (i.e.,amphiphilic polymers). Useful nonionic polymers include polyurethanederivatives such as PEG-150/stearyl alcohol/SDMI copolymer andPEG-150/stearyl alcohol SDMI copolymer. Other useful amphiphilicpolymers are disclosed in U.S. Pat. No. 6,010,541 incorporated byreference. Examples of anionic polymers that can be used as thickenersare acrylates copolymer, acrylates/ceteth-20 methacrylates copolymer,acrylates/ceteth-20 itaconate copolymer, and acrylates/beheneth-25acrylates copolymer. Aculyn® polymers sold by Rohm & Haas, as well ashair care materials, such as cationic resins, lanolin derivatives,cholesterol, pantothenic acids and betaine.

Alkalizing agents: Suitable materials that are used to increase pH ofthe hair dye compositions include ammonia, aminomethylpropanol,methylethanolamine, triethanolamine and ethanolamine.

Conditioners: Suitable materials include silicones and siliconederivatives; hydrocarbon oils; monomeric quaternary compounds, andquaternized polymers. Monomeric quaternary compounds are typicallycationic compounds, but may also include betaines and other amphotericand zwitterionic materials. Suitable monomeric quaternary compoundsinclude behentrialkonium chloride, behentrimonium chloride, benzalkoniumbromide or chloride, benzyl triethyl ammonium chloride, bis-hydroxyethyltallowmonium chloride, C12-18 dialkyldimonium chloride, cetalkoniumchloride, ceteartrimonium bromide and chloride, cetrimonium bromide,chloride and methosulfate, cetylpyridonium chloride, cocamidoproyplethyldimonium ethosulfate, cocamidopropyl ethosulfate,coco-ethyldimonium ethosulfate, cocotrimonium chloride and ethosulfate,dibehenyl dimonium chloride, dicetyldimonium chloride, dicocodimoniumchloride, dilauryl dimonium chloride, disoydimonium chloride,ditallowdimonium chloride, hydrogenated tallow trimonium chloride,hydroxyethyl cetyl dimonium chloride, myristalkonium chloride,olealkonium chloride, soyethomonium ethosulfate, soytrimonium chloride,stearalkonium chloride, and many other compounds. See WO 98/27941incorporated by reference. Quaternized polymers are typically cationicpolymers, but may also include amphoteric and zwitterionic polymers.Useful polymers are exemplified by polyquaternium-4, polyquaternium-6,polyquaternium-7, polyquaternium-8, polyquaternium-9, polyquaternium-10,polyquaternium-22, polyquaternium-32, polyquaternium-39,polyquaternium-44 and polyquaternium-47. Silicones suitable to conditionhair are dimethicone, amodimethicone, dimethicone copolyol anddimethiconol. See also WO 99/34770 published Jul. 15, 1999, incorporatedby reference, for suitable silicones. Suitable hydrocarbon oils wouldinclude mineral oil.

Natural ingredients: For example, protein derivatives, aloe, camomileand henna extracts.

Other adjuvants include acidulents to lower pH, buffers, chelatingagents antioxidants, sequestrants, etc. These classes of materials andother species of materials in the classes referred to above but notspecifically identified that are suitable are listed in theInternational Cosmetics Ingredient Dictionary and Handbook, (EighthEdition) published by The Cosmetics, Toiletry, and FragranceAssociation, incorporated by reference. In particular reference is madeto Volume 2, Section 3 (Chemical Classes) and Section 4 (Functions) areuseful in identifying a specific adjuvant/excipient to achieve aparticular purpose or multipurpose.

The above-mentioned conventional cosmetic ingredients are used inamounts suitable for their purposes. For example the wetting agents andemulsifiers are used in concentrations of from about 0.5 to 30 percentby weight, the thickeners are used in an amount of from about 0.1 to 25percent by weight and the hair care materials are used in concentrationsof from about 0.1 to 5.0 percent by weight.

The hair coloring compositions according to the invention can be weaklyacidic, neutral or alkaline according to their composition. Thecompositions typically have pH values of from 6.8 to 11.5. Their pH canbe adjusted in the basic range with ammonia. Also, organic amines can beused for this purpose, including monoethanolamine and triethanolamine,or also inorganic bases, such as sodium hydroxide and potassiumhydroxide. Inorganic or organic acids can be used for adjusting the pHin the acid range, for example phosphoric acid, acetic acid, citric acidor tartaric acid.

The hair coloring compositions of this invention will contain thecouplers of this invention, alone or in combination with other couplers,in an effective coloring amount, generally in an amount of from about0.01 to about 2.5 weight percent. Other couplers, when present will bepresent in an amount up to about 2.5 weight percent. The primaryintermediate(s) will generally be present in an amount of from about0.01 to about 3.5 weight percent. The molar ratio of primaryintermediate to coupler will generally range from about 5:1 to about 1:5and be employed in any suitable carrier or vehicle, generally an aqueousor hydroalcoholic solution, preferably an aqueous solution. The carrieror vehicle will generally comprise up to about 40 weight percent.

In order to use the oxidation hair coloring composition for dyeing hairone mixes the above-described hair coloring compositions according tothe invention with an oxidizing agent immediately prior to use andapplies a sufficient amount of the mixture to the hair, according to thehair abundance, generally from about 60 to 200 grams. Some of theadjuvants listed above (e.g., thickeners, conditoners, etc.) can beprovided in the dye composition or the developer, or both, depending onthe nature of the ingredients, possible interactions, etc., as is wellknown in the art.

Typically hydrogen peroxide, or its addition compounds with urea,melamine, sodium borate or sodium carbonate, can be used in the form ofa 3 to 12 percent, preferably 6 percent, aqueous solution as theoxidizing agent for developing the hair dye. Oxygen can also be used asthe oxidizing agent. If a 6 percent hydrogen peroxide solution is usedas oxidizing agent, the weight ratio of hair coloring composition andoxidizing agent is 5:1 to 1:2, but preferably 1:1. The mixture of theoxidizing agent and the dye composition of the invention is allowed toact on the hair for about 10 to about 45 minutes, preferably about 30minutes, at about 15 to 50° C., the hair is rinsed with water and dried.If necessary, it is washed with a shampoo and eventually after-rinsedwith a weak organic acid, such as citric acid or tartaric acid.Subsequently the hair is dried.

The hair coloring composition according to the invention with a compoundof formula (1) of this invention as coupler substances permits hairdyeing with outstanding color fastness, especially light fastness,fastness to washing and fastness to rubbing.

In general, a first composition of primary intermediate(s) andcoupler(s) is prepared and then, at the time of use, the oxidizingagents, such as H₂O₂, is admixed therewith until an essentiallyhomogenous composition is obtained which is applied to the hair to bedyed and permitted to remain in contact with the hair for a dyeingeffective amount of time, generally for a period of from about 2 to 45,preferably about 2 to 30, minutes, after which the hair is rinsed,shampooed and dried. Optionally, a separate conditioning product mayalso be provided. Together the hair dye composition of the presentinvention comprising the hair dye coupler (1) and the developercomprising the oxidizing agent form a system for dyeing hair. Thissystem may be provided as a kit comprising in a single package separatecontainers of the hair dye compositions, the developer, the optionalconditioner or the hair treatment product, and instructions for use.

EXAMPLE 9

The following compositions shown in Table 1 can be used for dyeingPiedmont hair. The dyeing solution is mixed with 100 g 20 volumehydrogen peroxide. The resulting mixture is applied to the hair andpermitted to remain in contact with the hair for 30 minutes. This dyedhair is then shampooed and rinsed with water and dried.

TABLE 1 Composition for Dyeing Hair Ingredients Range (wt %) Weight (%)Cocamidopropyl betaine  0-25 17.00  Monoethanolamine¹  0-15 2.00 OleicAcid  2-22 0.75 Citric Acid 0-3 0.10 28% Ammonium hydroxide¹  0-15 5.00Behentrimonium chloride 1-5 0.50 Sodium sulfite 0-1 0.10 EDTA 0-1 0.10Erythorbic acid 0-1 0.40 Ethoxydiglycol  1-10 3.50 C11-15 Pareth-9(Tergitol 15-S-9) 0.5-5   1.00 C12-15 Pareth-3 (Neodol 25-3) 0.25-5  0.50 Isopropanol  2-10 4.00 Propylene glycol  1-12 2.00P-Phenylenediamine² 0-5 2 mmoles N,N-Bis(hydroxyethyl)-p-phenylene 0-5 2mmoles diamine² 3-Methyl-p-aminophenol² 0-5 1 mmoles p-Aminophenol² 0-55 mmoles Coupler of this invention 0.5-5   5 mmoles 5-Amino-2-MethylPhenol 0-5 2 mmoles 2,4-Diaminophenoxyethanol 0-5 2 mmoles Water qs to100.00 qs to 100.00 ¹In the aggregate, these ingredients are in therange of 2 to 15% by weight. ²At least one of these dye precursors istypically present.

Exemplary combinations of hair coloring components employing a couplerof formula (1) of this invention are shown in combinations C1 to C126 inTable A. Reading down the columns in Table A, the Xes designate the dyecompounds (including the novel couplers of the instant invention) thatform illustratively suitable combinations of dyes that can be formulatedaccording to the present invention. For example, in Combination No. C1in Column 4 of Table A, a coupler compound of Formula 1 of thisinvention, wherein X, R, R¹, and R² are as defined hereinbefore, can becombined with p-toluene diamine and 2-amino-phenol. Especially preferredas the coupler compound in the combinations in Table 1 and in C1 to C126of Table A are:

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumiodide;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumchloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniummethyl sulfate;

{4-[3-hydroxy-4-hydroxyethyl-phenylamino)-methyl]-phenyl}-trimethylammonium chloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-triethyl ammoniumchloride;

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-tripropyl ammoniumpropyl sulfate;

{4-[3-hydroxy-4-ethyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumchloride; and

{4-[3-hydroxy-4-methyl-phenylamino)-methyl]-phenyl}-trimethyl ammoniumbromide.

TABLE A DYE COMBINATIONS Structure IUPAC Name Name C1 C2 C3 C4 C5 C6 C7C8 C9 C10 C11

3-Hydroxy-4-alkyl- phenylamino-methyl-1- alkyl-pyridinium halide X X X XX X X X X X X

2-Methyl-benzene- 1,4-diamine p-Toluene-diamine X X X X X X X X X

Benzene-1,4-diamine p-Phenylene-diamine X X

2-[(4-Amino-phenyl)- (2-hydroxy-ethyl)- amino]ethanol N,N-Bis(2-hydroxyethyl)-p- phenylene-diamine

4-Amino-phenol p-Aminophenol

4-Amino-3-methyl- phenol 3-Methyl-p- aminophenol

2-Amino-phenol o-Aminophenol X X

Benzene-1,3-diol Resorcinol X X

2-Methyl-benzene- 1,3-diol 2-Methyl-resorcinol X

Naphthalen-1-ol 1-Naphthol X

2-Methyl-naphthalen- 1-ol 2-Methyl-1-naphthol X

2-(2,4-Diamino- phenoxy)-ethanol 2,4-Diamino- phenoxyethanol X

Benzene-1,3-diamine m-Phenylenediamine X

3-Amino-phenol m-Aminophenol X

5-Amino-2-methyl- phenol 2-Hydroxy-4- aminotoluene X

2-(4,5-Diamino- pyrazol-1-yl)-ethanol 1-Hydroxyethyl-4,5-diamino-pyrazole Structure C12 C13 C14 C15 C16 C17 C18 C19 C20 C21 C22C23 C24 C25 C26

X X X X X X X X X X X X X X X

X X X X X X X X

X X X X X X X

X X X X X X X X

X

X

X X

X X

X X

X X

X X

X X

X

Structure C27 C28 C29 C30 C31 C32 C33 C34 C35 C36 C37 C38 C39 C40 C41

X X X X X X X X X X X X X X X

X X X X X X

X X X X X X X X X

X X X X X

X X X X X X X X X X

X X

X X

X X

X X

X X

X

X

X

X X

Structure C42 C43 C44 C45 C46 C47 C48 C49 C50 C51 C52 C53 C54 C55 C56

X X X X X X X X X X X X X X X

X X X X

X X X X X X X X X

X X X X X X X X X X X X X

x X

X x

X x

X

X

X

X X

X X

X X

X X

Structure C57 C58 C59 C60 C61 C62 C63 C64 C65 C66 C67 C68 C69 C70 C71

X X X X X X X X X X X X X X X

X X X X X X X

x X X X X X X X

x

x

x x

x x

x x

x x

x x

x x

x

Structure C72 C73 C74 C75 C76 C77 C78 C79 C80 C81 C82 C83 C84 C85 C86

X X X X X X X X X X X X X X X

x X X X X X X X X X X X X X

x X X X X X X X X

X X X X X X

x X

x X

x X

x X

x X

x

x

x

x x

Structure C87 C88 C89 C90 C91 C92 C93 C94 C95 C96 C97 C98 C99 C100 C101

X X X X X X X X X X X X X X X

X X X X X X X X X

X X

X X X X

X X X X

X X

X X

X

X

X

X X

X X

X X

X X

X X X X X X X X X X X Structure C102 C103 C104 C105 C106 C107 C108 C109C110 C111 C112 C113 C114 C115 C116

X X X X X X X X X X X X X X X

X X X X X X X

X X X X X X X X

X

X

X

X

X

X

X

X X X X X X X x x x x x x x x Structure C117 C118 C119 C120 C121 C122C123 C124 C125 C126

X X X X X X X X X X

X

X X X X X X X X X

x

x

x

x

x

x

x

x

x

x x x x x x x x x x

EXAMPLE 10 Dyeing Experiment

Piedmont hair weighing from 700 to 900 mg was used. Solutions of theprimary intermediate and a coupler were prepared separately according tothe following procedure. The concentration of both the primaryintermediate (PPD, PAP or PTD) and the coupler of Example 1 was 0.025 M,each in a base consisting of ethanol 7.85 g, sodium laureth sulfate 10g, ascorbic acid 0.3 g, EDTA 0.3 g, ammonium hydroxide 8.13 g (28%), andwater to 100 g. A solution of the primary intermediate (0.5 mL) and thecoupler (0.5 mL) was mixed with 1 mL of 20 volume hydrogen peroxide. Themixture was applied to piedmont hair tresses mounted on a glass plateand then stored at 40° C. for 30 min, washed, shampooed, washed, anddried. Color was evaluated using the Minolta Spectrophotometer CM-3700d.The resulting colors obtained are summarized in the Table 1.

TABLE 1 CIEL*a*b* Values Primary Intermediate PAP PPD PTD Coupler L* a*b* L* a* b* L* a* b* Com- 60.18 3.58 17.86 42.58 4.32 10.25 47.34 5.8813.53 pound 7 PAP: 4-aminophenol, PPD: p-phenylenediamine PTD:p-toluenediamine

With the foregoing description of the invention, those skilled in theart will appreciate that modifications may be made to the inventionwithout departing from the spirit thereof. Therefore, it is not intendedthat the scope of the invention be limited to the specific embodimentsillustrated and described.

We claim:
 1. A compound of formula (1):

wherein X is selected from the group consisting of halogen and R⁵SO₄; R³is selected from the group consisting of C₁ to C₂ alkyl andhydroxyethyl; and R, R¹, R² and R⁵ are each independently selected fromthe group consisting of C₁ to C₂₂ alkyl or C₁ to C₂₂ mono ordihydroxyalkyl.
 2. A compound of claim 1 wherein X is selected from thegroup consisting of Cl, Br, I and R⁵SO₄ where R⁵ is a C₁ to C₃ alkylgroup; and R, R¹ and R² are each independently selected from the groupconsisting of C₁ to C₃ alkyl.
 3. A compound of claim 2 wherein X is Cl,Br or R⁵SO₄, and R, R¹ and R² are each methyl.
 4. A compound of claim 2wherein X is Cl.
 5. A compound of claim 2 wherein X is R⁵SO₄.
 6. Acompound of claim 5 wherein R⁵ is methyl.
 7. A process for thepreparation of a compound of claim 1 comprising reductive amination ofan aminophenol of formula (2)

with a disubstituted aminobenzaldehyde of formula (3)

to produce a compound of formula (4)

and reacting the compound of formula (4) with a quaternization reagentR-X to produce a compound of formula (1)

wherein X, R, R¹, R² and R³ are as defined in claim
 1. 8. A processaccording to claim 7 wherein X is selected from the group consisting ofCl, Br, I and R⁵SO₄ where R⁵ is a C₁ to C₃ alkyl group; and R, R¹ and R²are each independently selected from the group consisting of C₁ to C₃alkyl.
 9. A process according to claim 8 wherein X is Cl, Br or R⁵SO₄where R⁵ is methyl; and R, R¹ and R² are each methyl groups.
 10. Aprocess according to claim 7 wherein the reducing agent is selected fromthe group consisting of sodium borohydride, sodium cyanoborohydride, andsodium triacetoxyborohydride.